Window cleaning apparatus

ABSTRACT

Apparatus for simultaneously cleaning both sides of a window comprises master and slave magnetic cleaning units. When the cleaning units are aligned on opposite sides of the window, magnetic attraction causes the slave cleaning unit to press against and to slide on the outside of the window in response to corresponding movement of the master cleaning unit on the inside of the window. Self-contained cleaning fluid reservoirs in alternative embodiments of the cleaning units controllably dispense cleaning fluid onto the window surfaces in response either to gravity forces, controlled by orientation of the master unit with respect to the vertical, or to magnetic biasing means actuated by a control means on the master unit.

limited States Patent [1 1 De Carlo WINDOW CLEANING APPARATUS [76]Inventor: Joseph P. De Carlo, 200 Harding CL,

Centerport, NY. 11721 22 Filed: Oct. 7, 1971 [21] Appl. No.: 187,369

Related US. Application Data [63} Continuation-impart of Ser. No.21,050, March 19,

1970, abandoned.

[52] 11.8. C1, 401/10, l5/250.03, 15/220 A see) [ Sept. 18, 1973 PrimaryExaminer-Robert W. Michell Assistant Examiner-J. H. Wolff Att0rneyJames1-1. Callahan et a1.

[57] ABSTRACT Apparatus for simultaneously cleaning both sides of awindow comprises master and slave magnetic cleaning units. When thecleaning units are aligned on opposite sides of the window, magneticattraction causes the slave cleaning unit to press against and to slideon the outside of the window in response to corresponding movement ofthe master cleaning unit on the inside of the window. Self-containedcleaning fluid reservoirs in alternative embodiments of the cleaningunits controllably dispense cleaning fluid onto the window surfaces inresponse either to gravity forces, controlled by orientation of themaster unit with respect to the vertical, or to magnetic biasing meansactuated by a control means on the master unit.

4 Claims, 8 Drawing Figures PAIENTEDSEPI 8'975 sum. 1 or 5 wwwm W w @lWT mpW w @TW PAIEmEnsEH 3.759.621

SHEEI 2 OF 3 INVENTOR M05591 10. .06 @QQo WINDOW CLEANING APPARATUS IThis is a continuation-in-part of copending application Ser. No. 21,050,filed Mar. 19, 1970, now aban- 'doned.

BACKGROUND OF THE INVENTION This invention relates to window cleaningapparatus and more specifically to devices for simultaneously cleaningboth sides of a window by an operator on one side of the window.

Prior devices in this field have generally required special guide barspermanently mounted on the window frame. To avoid the expense ofpermanentinstallations, completely portable apparatus has beendeveloped. An example is the window washing device disclosed in U.S.Pat. No. 3,120,672, issued to P. F. DiCostanzo on Feb. I l, 1963. In theDiCostanzo device, an elongated tank unit carrying a supply of cleaningfluid is designed to travel on rollers along the top of the windowframe. Extensible flexible tubes extend from the tank unit on eitherside of the window and have permanent magnets covered by absorbentcleaning padsattached to their lower ends. Attraction between themagnets causes the pad on the outside of the window to press against theglass and to follow the interior pad as it is moved across the innersurface of the winow. Squeezing a rubber air bulb connected to the topof the tank forces fluid out of the tank, down the tubes, and out small.holes adjacent the cleaning pads onto the window surfaces. 7

Although the DiCostanzo device provides an effective means forsimultaneously washing both sides of'a window, it is limited to windowswhich can be opened to provide space to mount the tank unit on top ofthe frame. Thus, it cannot be used, for example,'on doublehung windowshaving a fixed upper sash or on the fixed center pane of so-calledpicture windows. Further- SUMMARY OF THE INVENTION Accordingly, it is anobject of the present invention to provide an improved portableapparatus for simultaneously cleaning both sides of a window of any typeby a person standing on the inside.

It is a further object of the invention to provide window cleaningapparatus of the type described with which the cleaning step can beperformed with the window shut.

A still further object of the invention is to provide improved apparatusfor simultaneously cleaning both sides of a window of the type usingmagnetic attraction to hold separate cleaning units in aligned relationon opposite sides of a window, in which the cleaning units haveabsorbent pads which are easily replaceable to permit rapid change-overfrom washing to drying steps.

It is a still further object of the present invention to provide windowcleaning units of thetype described and having self-contained cleaningfluid reservoirs from which cleaning fluid can be selectively andcontrollably dispensed upon both sides of the window.

It is a still further object of the present invention to accomplish allof the foregoing purposes with apparatus of extremely simple design andhaving a minimum number of parts for utmost economy of both initial costand operation.

The foregoing and other objects are achieved in the present invention byan apparatus comprising a pair of cleaning units. Each cleaning unitincludes a lightweight housing having a substantially flat face withmeans for detachably mounting an absorbent cleaning pad thereon.Magnetic holding means are mounted in the housing of each unit, themagnetic holding means of each unit being positioned relative to themagnetic holding means of the other unit so as to hold the units inplace by magnetic attraction after they have been placed in opposedalignment on each side of a window.

For convenience, one of the cleaning units is designated the master unitand is intended to be placed in contact with the more accessible surfaceof the window, usually the inside. The other cleaning unit is designatedthe slave unit and is placed opposite the master unit on the more remotesurface of the window, usually the outside. The flux density produced bythe magnetic holding means of both units is chosen to provide sufficientattractive force between the units to cause the slave unit on theoutside of the window to follow the master unit as the operator moves itacross the inside of the window.

Furthermore, the magnetic flux is distributed in at least two laterallyspaced-apart zones, the separation of the zones permitting themagneticattraction forces between units 'to develop moment forces on theslave'unit to cause it to remain in alignment when the master unit isgiven rotary as well as translatory motion.

Preferably, each cleaning unit includes a reservoir for cleaning fluidwithin the housing and a conduit leading from the reservoir to adjacentthe window surface for dispensing the cleaning fluid upon the window asneeded during the cleaning operation.

An important feature of the present invention is that simultaneousdispensing of cleaning fluid from the reservoirs of both units iscontrollable by the operator. In one preferred embodiment cleaning fluidcan be dispensed in response to gravity forces through a conduit leadingfrom a reservoir within the housing of each unit to a location adjacentone edge of the unit. When additional fluid is needed, the operatormerely rotates the master unit against the window until the dispensinglocation is below the reservoir. Because the magnetic flux between theunits is distributed in at least two spacedapart zones, the slave unitwill rotate in alignment with the master unit so that cleaning fluidwill be dispensed therefrom simultaneously with that from the masterunit. 1

In other preferred embodiments, cleaning fluid can be dispensed inresponse to magnetic biasing means actuated by a control means on themaster unit. Magnetic forces produced by the magnetic biasing means maybe used either directly to operate pumping means for forcing cleaningfluid from the reservoir through the dispensing conduit or indirectly tocontrol potential energy storage means which, in turn, produce thepumping pressure for forcing cleaning fluid through the dispensingconduit.

The pumping means in those embodiments where the magnetic biasing meansacts directly to force cleaning fluid through the dispensing conduit maycomprise collapsible containers for expelling fluid in response tocollapsing force exerted by the biasing means when actuated by amanually operated control means on the master unit. The collapsiblecontainers are preferably of the type having flexible walls, such asrubber or plastic bags. Alternatively, they may have one or more movablewalls, such as a cylinder containing a movable piston.

Regardless of the Structure of the collapsible containers, the magneticforce between biasing magnets in the master and slave cleaning unitsprovides the direct pumping force for dispensing cleaning fluid. Thedispensing pressure available varies directly with the field strength,and consequent attractive force, of the biasing magnets.

On the other hand, when the magnetic biasing means are used indirectlyto control potential energy storage means, the pumping pressure isdetermined by the stored potential energy. The function of the potentialenergy storage means is to amplify the effectiveness of the magneticbiasing means in dispensing the cleaning fluid, so that comparativelysmall and light-weight magnets can control relatively large pumpingpressures.

The potential energy storage means preferably includes a container ofpressurized propellant of the type used for so-called aerosoldispensers. The propellant, when released by a valve operated bymovement of the magnetic biasing means, provides the pressure fordispensing the cleaning fluid.

The potential energy storage means alternatively may comprise, forexample, electrical energy storage means, such as a battery, forpowering an electrically driven pump for dispensing cleaning fluid inresponse to a switch operated by movement of the magnetic biasing means.

In one preferred embodiment the cleaning fluid reservoir of each unititself comprises a collapsible container. A movable compression memberis disposed in the housing on the opposite side of the container fromthe face of the housing. Biasing magnets are mounted on the compressionmembers of each unit, the magnet in the slave unit being fixed and themagnet in the master unit being movable by manually operable controlmeans to selectively produce either attraction or repulsion magneticforces between the master and slave biasing magnets when theirrespective units are in alignment on opposite sides of a window.

In using this embodiment, the operator places the master and slavecleaning units in aligned relation on opposite sides of the window to becleaned with their absorbent pads contacting the window surfaces. As theoperator moves the master unit over the inside of the window, the slaveunit will follow in substantial alignment as a result of the attractionbetween the respective magnetic holding means in each unit.

When additional cleaning fluid is needed the operator merely adjusts thecontrol means on the master unit to position the biasing magnet in themaster unit in proper relation to the biasing magnet in the slave unitto produce attraction force between them. This attraction force biasesthe compression members against the respective collapsible containers,thus forcing cleaning fluid out through the dispensing conduits of eachunit. When sufficient cleaning fluid has been dispensed, the operatorreadjusts the control means to position the biasing magn et of themaster unit in repulsion relation with the biasing magnet of the slaveunit.

DESCRIPTION OF THE DRAWINGS Other objects, aspects and features of thepresent invention will be apparent from the following description anddrawings, in which:

FIG. 1 is a perspective view of a preferred embodiment of the inventionemploying direct-acting magnetic biasing means for dispensing cleaningfluid as it may be used to simultaneously clean both sides of a window;

FIG. 2 is a cutaway perspective view along lines 2--2 of FIG. 1, showingthe details of the fluid dispensing mechanism;

FIG. 3 is a cross-section along lines 33 of FIG. 1, showing the positionand operative relation of the magnetic holding means and fluiddispensing means;

FIG. 4 is a cross-section along lines 44 of FIG. 3;

FIG. 5 is a cross-section similar to FIG. 4 of an alternate embodimentof the invention;

FIG. 6 is a cross-section similar to FIG. 3 of another modifiedembodiment of the invention;

FIG. 7 is a cutaway perspective view of another embodiment of theinvention employing potential energy storage means controlled bymagnetic biasing means for dispensing cleaning fluid; and

FIG. 8 is a cross-section along lines 88 of FIG. 7, showing theoperating linkage between the magnetic biasing means and the pOtentialenergy storage means.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, andparticularly to FIGS. 1-4, the present invention comprises a mastercleaning unit 11 and a slave cleaning unit 12. In FIG. 1, the units areshown in operative relation on opposite sides of windowpane 14. The twounits are identical except for handles and a cleaning fluid dispensingcontrol means included in the master unit-only. Identical elements ineach unit are designated by the same reference number. For convenience,only the construction of master cleaning unit 11 will be described, itbeing understood that slave cleaning unit 12 is identical except wherenoted.

Master unit 11 includes an elongated hollew housing 15, which differsfrom housing 16 of slave unit 12 only in the provision for mountinghandles 17 and 18 and control means 20, elements which are not part ofslave unit 12. Housing 15 may be made of any suitable lightweightnonmagnetic material, such as molded plastic or aluminFm.

Housing 15 has a substantially flat face 22 with inwardly slopingflanges 24 extending along each longitudinal edge to form a shallow slotfor slideably receiving and holding an absorbent cleaning pad 26.

Inside housing 15, collapsible container 28 serves As a reservoir forcleaning fluid 30. Dispensing conduit 32 leads from collapsiblecontainer 28 outside housing 15 to a dispensing location adjacentabsorbent cleaning pad 26.

At either end of housing 15, magnetic holding means such as magnets 34and 36 are mounted with their pole faces adjacent housing face 22.Holding magnets 38 and 40 are similarly mounted in housing 16 of slaveunit 12 but, as shown in FIG. 4 with their pole faces arrangedoppositely to the pole faces of holding magnets 34 and 36. That is, theNorth seeking pole of holding magnet 38, for example, will be oppositethe South 34, 38 and 36, 40 will exert attractive forces upon each otherwhen cleaning units 11 and 12 are aligned with each other on oppositesides of window-pane 14.

As shown particularly in FIG. 2, a fluid dispensing means includes acontrol means 20, found onlyon master cleaning unit 11, such as, forexample, a dialing means such as disc 41 rotatably mounted on the back42 of housing by means of bushing 44. One end of square shaft 46 isslideably keyed into square hole 48 passing along the axis of bushing 44and partially into disc 41. The other end of square shaft 46 is fixed toa magnetic biasing means, such as magnet 50, which in turn contactsmovable compression member 52.

Slave cleaning unit 12 also has a magnetic biasing means such as magnet54 identical to magnet 52 of master cleaning unit 1 1 except that it isrigidly attached to an identical compression member 52. As shown moreclearly in FIG. 3, compression member 52 is free to slide toward andaway from housing face 22 on support rods 54 and 56.

Referring again to FIG. 2, biasing magnet 50 is affixed onto squareshaft 46 with an orientation such that when arrow 58 on disc 41 isaligned with dispensing conduit 32, the pole faces of magnet 50 arepositioned to produce maximum magnetic attraction with the pole faces ofbias magnet 54 in slave unit 1-2 when the two units are in alignment onopposite sides of window 14. That is, the North seeking pole of magnet50-will'be positioned opposite the South seeking pole of magnet 54, andvice versa.

Since both biasing magnets 50 and 54 are free to move with compressionmembers 52 in a direction per-v pendicular to housing faces 22, themagnetic attraction between them will urge compression members 52 ofboth master and slave cleaning units toward their respective housingfaces 22 and forcecleaning fluid 30 out of both collapsible containers28 through dispensing conduits 32 for application simultaneously to bothsides of windowpane 14. When sufficient cleaning fluid has beendispensed, the operator can rotate disc 41 a half turn so that alikepoles of magnets 50 and 54 are then in opposed relatiOn, therebyproducing repulsion magnetic forces between them and releasing thebiasing pressure on the collapsible containers 28.

In the magnetically actuated fluid dispensing means described above themagnetic force between the master and slave biasing magnets provides thedirect pumping force for dispensing the cleaning fluid from thereservoirs. In the specific embodiment of FIGS. 1-4, this magnetic forceacts on the entire fluid in each reservoir through the pressure ofcompression members 52 against collapsible containers 28. The pressuretransmitted to the fluid is equal to the attractive force between themagnets divided by the effective piston area ervoir. This allows theeffective piston area of the compression members to be quite small and,correspondingly, the biasing magnets to be relatively small andlightweight while still providing the desired fluid dispensing pressure.For example, the collapsible container can be sized to hold one squirtof cleaning fluid and be connected through a check-valved conduit to therest of the reservoir so as to be replenished from the main portion ofthe reservoir after each actuation of the control means.

Furthermore, although the collapsible containers 28 shown in theembodiment of FIGS. 14 are in the form of flexible-walled bags, theinvention is not limited to such construction. The collapsiblecontainers, for example, can be in the form of a cylinder and pistoncombination. The piston is connected by a piston rod to the biasingmagnet and serves as a compression member to pump fluid contained in thecylinder through the dispensing conduit in response to actuation of thecontrol means. The cylinder can be replenished through conduits leadingto the main reservoir, and various valve arrangements well known in theart can be used to provide single-acting or double-acting pumpoperation, as desired.

Referring next to FIG. 5, a modification of the preferred embodiment isshown which makes use of gravitational rather than magnetic force todispense cleaning fluid from a self-contained reservoir. In thisembodiment, the master and slave cleaning units are identical in allrespects, with the possible exception of optional handles (not shown)for use with the master unit. All elements of these units are the sameas corresponding elements in the previously described embodiment exceptfor the.,dispensing mechanism, so only that feature will be described.

Within elongated hollow housings 60 of both master and slave cleaningunits, cleaning fluid reservoirs 62 are filled through any suitablemeans, such as a stoppered hole (not shown), with cleaning fluid 30. Foruse, the master and slave units are placed, as described above, inaligned relation on opposite sides of windowpane 14.

In normal use, the units will be aligned with dispensing conduits 32positioned above the housings 60. When additional cleaning fluid isneeded, the operator merely rotates the master unit a half turn on theinside of the window to place dispensing conduit 32 below housing 60, asshown in FIG. 5. Because of the attraction between the magnetic holdingmeans Of the two units, as previously described, the slave cleaning unitwill remain in substantial alignment with the master unit so that itsdispensing conduit will also be rotated to a position below its housing60. When sufficient cleaning fluid 30 has flowed down and out ofdispensing conduits 32 under the influence of gravity, the operator willrotate the master unit another half turn to again position bothdispensing conduits 32 above housing 60.

In this connection it should'be noted that by using a pair of holdingmagnets, one in each end of the housing, spaced-apart magnetic fluxzones are created which permit substantial moment force to be developedtending to rotate the slave unit when the master unit is rotated. Itwill be apparent that the same effect could be obtained by using asingle magnet in each unit having its poles spaced a substantialdistance apart, such as a long bar magnet.

Referring to FIG. 6, another modification of the preferred embodiment isshown having no self-contained reservoir. This embodiment is intendedfor use with smaller windows which can be cleaned by saturating theabsorbent cleaning pads once in a bucket of cleaning fluid; positioningthe cleaning units in aligned relation on opposite sides of the window;wiping the master unit over the inside surface, with the slave unitsimultaneously washing the outside surface; removing the units from thewindow; replacing the wet pads with clean dry pads; and then drying thewashed window by the same process.

The embodiment of FIG. 6, by not including a selfcontained reservoir ofcleaning fluid, can use smaller magnets than the previously describedembodiments, but in other details it is similar to those embodiments andwill not be separately described here. It should be noted, however, thatthe embodiment of FIG. 6 includes the feature of the spaced-apartmagnetic holding means of the invention; so that the slave unit willeasily follow any rotary motion of the master such as nor mally occursin the sweeping motions used in washing windows. Thus, the holdingmagnets of the two units will not rotate out of alignment during thecleaning operation with resultant loss of holding force exerted o theslave unit.

In the alternate preferred embodiment shown in FIGS. 7 and 8, the fluiddispensing means includes potential energy storage means, such asidentical containers 70 for pressurized propellant fluid, in both themaster unit 72 and slave unit 74 for providing the pumping pressure todispense cleaning fluid from identical reservoirs 76. Magnetic biasingmeans, such as magnets 78 and 80 in the master and slave units,respectively, are connected through identical levers 82 to control theoperation of conventional aerosol valves 84 mounted on containers 70.When opened, valves 84 permit pressurized propellant to flow fromcontainers 70 through conduits 86 to reservoirs 76, thereby displacingcleaning fluid from the reservoirs through dip tubes 88 and outdispensing conduits 32.

To actuate the fluid dispensing means of this embodiment, the operatorpresses a control means, such as push button 90 extending through thetop of master unit 72 and conneted to biasing magnet 78. Downward motionof biasing magnet 78 pivots lever 82 about pin 92 to open valve 84 inthe master unit. At the same time, the magnetic attraction forcesbetween biasing magnet 78 in the master unit and biasing magnet 80 inthe slave unit cause magnet 80 to move downward and actuate Valve 84 inthe slave unit in a similar manner. All other features necessary foroperation of the embodiment of FIGS. 7 and 8, such as magnetic holdingmeans (not shown) mounted in end compartments 94 and 96 are similar tothose in previously described embodiments and will not be describedhere.

Although the preferred embodiments have been illustrated and describedabove, it will be understood that the invention is not so limited. Forexample, electromagnets can be used in place ofthe permanent magnetsshown, and the shape of the housing and positioning of the magnets canbe varied without departing from the principles of the invention.

Furthermore, different linkage arrangements are possible for usingmovement of the magnetic biasing means to control, either directly orthrough the amplifying power of potential energy storage means, theselective dispensing of cleaning fluid from the reservoirs of bothmaster and slave unit. For example, the fluid dispensing means of masterand slave units can be made to operate independently by disconnectingthe magnetic biasing means of the master unit from the fluid dispensinglinkage of that unit and having separate control means for each.

Similarly, in those embodiments in which the magnetic biasing meansoperate pumping means directly to dispense cleaning fluid, the pumpingmeans of the master unit can be independent of operation of the magneticmeans and be manually operable as, for example, by a push button actingagainst a collapsible container. The magnetic biasing means of bothunits would then be used only to operate the pumping means of the slaveunit.

In addition, the invention covers the placement of fluid dispensingmeans in the slave unit only, if desired for reasons of economy, sincethe window surface cleaned by the master unit is accessible forapplication of cleaning fluid from a separate container or applicator.

What is claimed is:

1. Apparatus for simultaneously cleaning both interior and exteriorsurfaces of a window comprising a master cleaning unit and a slavecleaning unit, each unit including:

a' housing having a substantially flat face;

an absorbent cleaning pad removably mounted on said housing face;

magnetic holding means mounted in said housing, the

magnetic holding means of the master cleaning unit being disposedrelative to the magnetic holding means of the slave cleaning unit so asto produce sufficient attractive force between said magnetic holdingmeans when said master and slave cleaning units are aligned on oppositesides of the window with said absorbent cleaning pads contacting thewindow surfaces to cause said slave unit to move in alignment with themaster unit when the master cleaning unit is moved over one surface ofthe window;

fluid dispensing means in at least said slave unit comprising acollapsible container for cleaning fluid contained within said housingand a conduit leading from said container to the exterior of saidhousing adjacent the cleaning pad for applying the cleaning fluid to thesurface of the window; said master cleaning unit further comprises amaster magnetic biasing means mounted within the housing for providing aselectively variable magnetic flux field and manually-operated controlmeans connected to the master magnetic biasing means for selectivelyvarying the magnetic flux field induced by the master magnetic biasingmeans; and

said slave cleaning unit further comprises a slave magnetic biasingmeans disposed within the housing for movement toward or away from saidcollapsible container of said slave unit in response to the selectivelyvariable magnetic flux field induced by the master magnetic biasingmeans when the master and slave cleaning units are aligned on oppositesides of the window with said absorbent pads contacting the windowsurfaces, whereby the cleaning fluid in the collapsible container of theslave unit is selectively forced through the conduit for application tothe surface of the window in response to operation of the master unitcontrol means.

2. The apparatus of claim 1 wherein said manually-operated control meansselectively reverses the magnetic flux field induced by the mastermagnetic biasing means, and

said slave magnetic biasing means comprises a magnet disposed on theopposite side of the collapsible container from the slave unit housingface for movement selectively toward and away from said face in responseto the selectively reversible magnetic flux field of the master magneticbiasing means.

3. The apparatus of claim 2 wherein said master and slave units bothinclude said fluid dispensing means and said master magnetic biasingmeans comprises a magnet slideably mounted within the master unithousing on the opposite side of the collapsible container from thehousing face for movement toward and away from said face.

4. The apparatus of claim 3 wherein the manually operable control meansof the master cleaning unit comprises:

dialing means rotatably mounted on the back of the housing for rotationone-half turn about an axis substantially perpendicular to the face ofthe housing and means for mounting the master biasing magnet, saidmounting means being slideably keyed to said dialing means for rotationby said dialing means and translation toward and away from said dialingmeans along said axis of rotation, whereby the biasing magnet of saidmaster cleaning unit is selectively rotatable one-half turn in responseto rotation of said dialing means to reverse the position of the polesof the master biasing magnet.

1. Apparatus for simultaneously cleaning both interior and exteriorsurfaces of a window comprising a master cleaning unit and a slavecleaning unit, each unit including: a housing having a substantiallyflat face; an absorbent cleaning pad removably mounted on said housingface; magnetic holding means mounted in said housing, the magneticholding means of the master cleaning unit being disposed relative to themagnetic holding means of the slave cleaning unit so as to producesufficient attractive force between said magnetic holding means whensaid master and slave cleaning units are aligned on opposite sides ofthe window with said absorbent cleaning pads contacting the windowsurfaces to cause said slave unit to move in alignment with the masterunit when the master cleaning unit is moved over one surface of thewindow; fluid dispensing means in at least said slave unit comprising acollapsible container for cleaning fluid contained within said housingand a conduit leading from said container to the exterior of saidhousing adjacent the cleaning pad for applying the cleaning fluid to thesurface of the window; said master cleaning unit further comprises amaster magnetic biasing means mounted within the housing for providing aselectively variable magnetic flux field and manually-operated controlmeans connected to the master magnetic biasing means for selectivelyvarying the magnetic flux field induced by the master magnetic biasingmeans; and said slave cleaning unit further comprises a slave magneticbiasing means disposed within the housing for movement toward or awayfrom said collapsible container of said slave unit in response to theselectively variable magnetic flux field induced by the master magneticbiasing means when the master and slave cleaning units are aligned onopposite sides of the window with said absorbent pads contacting thewindow surfaces, whereby the cleaning fluid in the collapsible containerOf the slave unit is selectively forced through the conduit forapplication to the surface of the window in response to operation of themaster unit control means.
 2. The apparatus of claim 1 wherein saidmanually-operated control means selectively reverses the magnetic fluxfield induced by the master magnetic biasing means, and said slavemagnetic biasing means comprises a magnet disposed on the opposite sideof the collapsible container from the slave unit housing face formovement selectively toward and away from said face in response to theselectively reversible magnetic flux field of the master magneticbiasing means.
 3. The apparatus of claim 2 wherein said master and slaveunits both include said fluid dispensing means and said master magneticbiasing means comprises a magnet slideably mounted within the masterunit housing on the opposite side of the collapsible container from thehousing face for movement toward and away from said face.
 4. Theapparatus of claim 3 wherein the manually operable control means of themaster cleaning unit comprises: dialing means rotatably mounted on theback of the housing for rotation one-half turn about an axissubstantially perpendicular to the face of the housing and means formounting the master biasing magnet, said mounting means being slideablykeyed to said dialing means for rotation by said dialing means andtranslation toward and away from said dialing means along said axis ofrotation, whereby the biasing magnet of said master cleaning unit isselectively rotatable one-half turn in response to rotation of saiddialing means to reverse the position of the poles of the master biasingmagnet.